Author Topic: RLE Last & First  (Read 13390 times)

Offline Jasonb

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RLE Last & First
« on: July 22, 2023, 07:24:34 PM »
In a departure from my usual practice of not posting a build thread until an engine has at least been test run I'm going to make an exception with this one. Graham Corry of Alyn Foundry & Sons has announced this week that there will be a new batch of castings being done for his popular "RLE" design of hit and miss engines. For those that don't follow Alyn's Facebook page and who may want to secure a casting set then make contact via this e-mail address and you can check the price and place your deposit. alynfoundry103@gmail.com. Hopefully most of this thread should be complete and act as a guide to anyone who decides to order an RLE.

I got most of a set of castings for this engine a couple of months ago which Graham managed to cobble together from his last few remaining castings with the exception of the flywheels which will be getting cast along with the new batch of kits so that will likely make this the last supplied with castings from the old foundry and no doubt rammed up by Graham himself.

This will also be the first engine to be built to a new set of drawings as the original set leave a bit to be desired in this day and age. They will also be in metric which will hopefully attract some of the newcomers into the hobby who have been brought up with the metric system and have tooling and machines based on that system rather than Bananas.

The new drawings set will also take into account the newer carb design and show modified rocker arm, rocker bracket, cam and head details to suit it's straight vertical pipe entry. It will show the MOD gears, metric fixings, O ring for the piston and a fuel tank (No Baccy tins from now on) as well as optional square push rod and governor balance weight designs. Lastly there will be details of a cart with hopefully the addition of cast cart wheels and axle brackets and a spoke mounted pulley casting that will be available as extras.

I have been modelling the engine as work progresses making adjustments to suit how the castings machine up as I go, this is the state of play so far.



That's enough of the intro, time for some swarf :)

Starting with the base casting after a light fettling it was shimmed up on the mill table to get the sides tapering equally and the bottom flange milled flat using an insert facemill. While still held in position by the two clamps on the inside a round disc was held in the mill spindle to help best locate the centre of the two cast bosses.



After spotting and drilling for the hold down holes I ran around the edge to just clean up the flange so it was straight enough to use as a reference surface, you may also be able to see that I have milled the internal fillets to the left boss stopping at a scribed line that was done around the disc at the time of locating it which can be used as a guide to trim the bosses to a more attractive shape.



Now that the base had a flat bottom it could be clamped to the mill table, the skimmed flange edge set true and the upper surface machined again with the facemill. You may notice I am using polished inserts intended for aluminium and non ferrous on this cast iron part as I find the sharper inserts put a lot less strain on the lower powered and less rigid benchtop mills than the standard inserts do. The carbide will also cope a lot better should there be any hard areas in the castings which was not a problem with these specially coated Welsh products.  ;)



I left out drilling and tapping the four holes to mount the crankcase until I had machined that but they could be put in now working to the sizes on the new drawing. A bit more fettling of the surfaces and clean up of the corners was done as well as spot facing the two mounting bosses before moving on to the next part.






Offline mikehinz

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Re: RLE Last & First
« Reply #1 on: July 22, 2023, 07:34:42 PM »
Jason, a very nice start to an interesting project!  I'll be following!  Hopefully I'll pickup a few tips along the way.

Thanks!

Mike
MIke
Wichita, KS, USA

Offline Alyn Foundry

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Re: RLE Last & First
« Reply #2 on: July 23, 2023, 12:08:20 PM »
Thanks Jason.
The boys, Roy, Mathew and Alan have asked me to thank you personally for the help in getting Alyn Foundry and sons Ltd moving again. I have to say that in these very different times with massively improved communications they’re already processing their fourth order. It took me several months to get to the same level.

The R.L.E. as most people know was a “ scratch built “ design. It embodied many attributes of the traditional agricultural engines in preservation, seen on the rally fields around the country. It was described by many as a rather crude example of an engine design but from a famous automotive quote
“ It’s crude but it works “ There have been many engines built over the years and no two are exactly the same. The R.L.E. allowed the constructor free rein to alter and adapt it to their taste. I have seen one with a sideshaft and face cam valve opening and just recently Alan has finished his own, very quirky engine fitted with hydraulic valve opening and hot tube ignition.

Funnily enough there have also been enquiries about the R.L.E. in its original air cooled format.

Well that’s all from me I look forward to seeing and reading your thread as it unfolds. It’s such a pity that the boys couldn’t offer the kit at the original price back in the day. Sadly all foundries have been hit very heavily with various environmental taxation and material costs have skyrocketed.

As a footnote I will be particularly interested to read about the timing gears. We used to use the services of HPC gears and by bulk buying were able to offer them at quite reasonable prices. With the advent of the Far Eastern market I have just ordered 2 pairs of 0.5 MOD gears for the price one, single gear from here in the UK.

 :cheers:  Graham.
« Last Edit: July 23, 2023, 12:19:01 PM by Alyn Foundry »

Offline Jasonb

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Re: RLE Last & First
« Reply #3 on: July 23, 2023, 05:07:58 PM »
Thanks Graham, good to hear sales are off to a flying start no doubt helped by goodwill which I hope you are being adequately rewarded for ;)

I've been smoothing out a few of the Crude bits on mine but you know I like a slightly more fettled look than you :) Actually they are nice castings and it is more just personal tweaks and additions than anything wrong with the basic engine.

I opted to cut my own gears though I did use very reasonably priced far eastern cutters. I have also adjusted widths to match the commercially available MOD gears from several sources so anyone wanting to buy them can do so and won't need to add anything to the width which is always harder than taking a bit off which would have been the case if I just picked the nearest metric equivalent width. Tooth count has also been picked so there are more options of sellers than picking the nearest to the 1" ctrs.

Offline Admiral_dk

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Re: RLE Last & First
« Reply #4 on: July 23, 2023, 09:35:49 PM »
Great to hear that buisiness is of to a good start   :ThumbsUp:   :ThumbsUp:

Quote
a famous automotive quote “ It’s crude but it works “

Kind of similar to one of my favourites "KISS - Keep It Simple Stupid" .... as all extras, also give more possible faults to happen ....  :cheers:

Per

Offline Jasonb

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Re: RLE Last & First
« Reply #5 on: July 25, 2023, 07:43:28 PM »
The cylinder casting was given a light fettle so I could take a few measurements and have reasonable surfaces to hold before being put into the 3-jaw and set so the three "rings" ran as true as possible. I then took a couple of light passes across the end to clean remove the draft angle and leave a clean surface. While in the chuck I also just cleaned up the middle ring to give me something to clock true and also run a steady on if I felt the need for one.



I've seen a lot of people use the 4-jaw and a steady to do the boring of the cylinder but I opted to clamp the freshly machined end to the faceplate, tapping the casting until the central ring ran true. The end was cleaned up both on the face and OD and then I used a 16mm boring bar with CCGT insert to bore to the required 33mm.



I did not do any more work on the cylinder but left it fixed to the faceplate while I made a start on the hopper. Again after a bit of a fettle and some measuring up I hot glued a couple of pieces of scrap aluminium to each end and marked out the centre of the bosses. The casting was then packed up and clamped to the lathe's cross slide and the position adjusted so the marks lined up with head and tailstock ctrs. I find this type of setup preferable to having an unbalanced lump in the 4-jaw and the between ctrs boring bar that will be used doe snot flex as much as a toolpost mounted one can do so you get a straighter bore. Not the ideal clamp positions but it was solid enough.





Initial cuts to enlarge the cored hole were done with a boring head. Then I switched a 28mm between ctrs bar, well actually between chuck and tailstock bar to take the hopper ends out to the required 54mm dia. Once this had been done I changed to a tool with it's cutting edge at 90deg to the bar's axis to face off the boss that will face towards the crank.



Now that I had a known bore I used the hopper as a gauge to get the final size of the cylinder, seems about right as it stays horizontal without swinging down but can be pushed on by hand.



I'll leave bonding the two together until a bit more work has been done.

Quick video of some of the operations described above.

<a href="https://www.youtube.com/watch?v=5wC7_IauokM" target="_blank">http://www.youtube.com/watch?v=5wC7_IauokM</a>



« Last Edit: July 25, 2023, 07:49:36 PM by Jasonb »

Offline Amblejo1

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Re: RLE Last & First
« Reply #6 on: July 27, 2023, 11:53:55 AM »
To see Jason's machining skills is truly inspiring, and such good news to hear that Alyn Foundry is back with us in the capable hands of "and Sons" who have already been very helpful to me regarding my 2005 vintage Gardner casting kit which I am returning to after a very busy first half of the year on our smallholding. Power to your elbows chaps  :)

Offline Jasonb

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Re: RLE Last & First
« Reply #7 on: July 30, 2023, 06:56:13 PM »
Thanks

Before machining the main crankcase casting of the RLE it is worth getting the bearing caps ready. These are supplied as one so after a skim cut to flatten the bottom and then the ends with the now flat bottom against the vice fixed jaw the casting can be cut in two. Well actually you can cut it into three as there is plenty of length and it's quicker to saw away a waste piece than turn it into chips.

I can see how Graham made the pattern many moons ago simply by gluing a piece of half round timber moulding onto a flat piece and adding a bit of draft around the edges. This gives the profile shown top right in the following photo and if we assume the radius of the "hump" is where the green sharpie mark is then most of the material needs to come off the bottom which combined with a bit of flattening of the hump results in the section shown top left. I went a bit further and used the excess height of the hump to provide enough material to form a boss that can later be drilled and tapped for an oil pot - middle bottom. Clearance hole scan be drilled and spot faced so the caps are ready for when they are needed.



The crankcase was shimmed up on the mill table to get it to sit nice and level and not be distorted by clamping pressure and the facemill used to flatten it's bottom. Now that I had a solid surface it could be set up on the table with some parallel packing below and set to get the best centre line of the casting in line with the mill's X-axis. I started out buy locating the four hold down bolt holes so they sat reasonably central to the cast bosses noting their positions on the DRO before spot facing to give the nuts a good surface to tighten down onto.



Next the vertical face that the cylinder flange mates to was squared up, just taking off the bare minimum at the top and down low enough that the flange clears the step left by machining away the draft angle. I later blended that small step in to leave a smooth fillet where the vertical meets the horizontal as I'm fussy like that..



Moving to the other end of the casting the bearing split line was milled down to the required 41mm above the bottom of the base and the stud holes drilled and tapped M4. You can see in the photo that I'm using a spiral flute tap, I've almost gone over to these exclusively as they cut well, clean out the swarf as they go and it means you only need to tap once not two or three times as you do with the usual set of three taps.



For the following operations I like to use a machining plate as it gives good flat surfaces that you can run a DTI against when setting up the irregular shaped casting and also gives a good surface to clamp down.

Here I have clocked the long edge of my well used machining plate true along the mill's X-axis, located that edge and established my ctr line a known distance from it (50mm in this case) and then using the previously noted DRO positions drilled and tapped so the casting can be screwed to the plate. The bearing caps were then screwed into place ready for boring.



Knowing the exact lathe ctr height above my cross slide and the thickness of the plate it was simple to work out how much packing was needed to bring the bearing split line upto ctr height, clock the edge of the plate true across the lathe and then start machining. First I used a 16mm 4-flute cutter to produce a flat edge by machining away the draft on the base and stopping just as the cutter touched the bearing cap. I followed up with a 6mm ctr cutting 3-flute cutter to remove the pip left by the conventional non ctr cutting endmill.



This flat surface could then be spot drilled followed by a 6mm stub drill and then the far end was done with long series ctr and 6mm drills. Following that a spot facer I had made for a previous engine was used to flatten the remaining three faces.



I could then drill out 10mm followed by reaming size for 12mm. If you want to take the option of having the crankshaft run in the cast iron then just drill to 9.7mm and then ream 10mm



A machine reamer was used to finish the holes to 12mm ready to accept the bearings.





That's enough for one night, next time the crankcase can be completed and these three main castings brought together. In the meantime a quick vid of the drilling and boring on the lathe and no the reamer is not going backwards!

<a href="https://www.youtube.com/watch?v=JIiLPLkGVEU" target="_blank">http://www.youtube.com/watch?v=JIiLPLkGVEU</a>
« Last Edit: July 30, 2023, 07:01:22 PM by Jasonb »

Offline Jasonb

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Re: RLE Last & First
« Reply #8 on: August 03, 2023, 06:54:03 PM »
While the crankcase was still mounted to the machining plate I clocked it vertical on the mill, located ctr and cylinder height and then off set each side to drill and tap for the two studs to hold the cylinder in place



Once I knew the ctr to ctr distance of these holes I did the clearance ones in the cylinder's flange. When it was in the lathe I had scribed a horizontal line at mid point across the flange. Here I have clamped a parallel to that scribed line and clocked it true along the X-axis, located ctr of bore and then offset each side to drill the holes



While held like this I used a smaller homemade reverse spot facing tool to machine a nice surface for the nuts to sit on.



Using the heads of a couple of cap head screws poked into the holes and resting them on a parallel the cylinder could be clamped horizontal to an angle plate to flatten the area around the lubricator hole which was also drilled and tapped.



Next was to bond the hopper onto the cylinder, I opted for high temp Loctite 648 on the cylindrical surfaces and a small amount of JB Weld on the radial step towards the crank end of the hopper. To make sure the hopper was sitting upright I mounted the crankcase to the base and the cylinder to the case, a couple of stops in a tee slot set the base true along the X-axis and then an edge finder between the two bearing caps set the engines ctr line in Y. You may just be able to see at the top edge of the image towards the right hand side a pointer in  the mill spindle, this was lined up with the central parting line of the hopper so all was centred up and left to set.



After a couple of days the hopper and cylinder were machined to final length at the head end, quite happy with the joint which can barely be seen.




Offline Jasonb

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Re: RLE Last & First
« Reply #9 on: August 07, 2023, 07:17:18 PM »
I suppose the cylinder head is the next logical casting to get out the way. After a quick clean up I made a start by holding it in the 4-jaw slipping a parallel under each of the stud bosses in turn to make sure the outer cast surface was reasonably true across the lathe's axis and than machined the underside of the head so I had a good flat surface to work with. I also took the smallest of cuts off the OD to get the head round but not far enough up the sides to remove the draft angle.



Next the head was clamped to the mill table on a piece of MDF, I held a straight edge against the two valve bosses and eyed that up along the X-axis so the valves would sit horizontally. Then the three ends of the "Tee" where milled flat, the inlet and exhaust ones just want the minimum taking off so you get as much thread depth as possible for the pipes but the one for the rocker bracket should be machined to dimension. The clamps will need moving about to allow access to all three faces. The tops of the valve bosses can also be leveled off at this stage.

The bosses for the four head studs are not equally spaced around the head so I spend a bit of time getting the best centre for each boss and noting the DRO readings before spot facing and drilling 4mm. Ignore the fact they are tapped in the photo, I was going to hold the head one way for the next op but did it another.



I like to do the valve guide, valve cavity and valve seat on the lathe rather than use  a CSK bit in the mill which can chatter and I've not yet had to make a valve seat cutting tool for any of my engines doing the seats with the topslide set over. So I made some simple standoffs from tube and screwed the head to a scrap piece of square aluminium plate which could then be held in the 4-jaw to position each valve hole in turn.



The square piece of plate also made it easy to index the head around to drill and tap the inlet and exhaust connections. The M3 tapped hole for the rocker could also be done at this stage though I did mine later as I wanted to tweak the rocker post casting to suit having the exhaust valve on the far side



Still holding you the plate the spark plug hole was drilled, spot faced and then tapped M10 x 1 for a CM-6 plug



When I did get round to doing the holes for the rocker post this is how I set it up to do the tapped hole using two drill bit sin the valve holes to set the work vertical and then using the side of a drill bit to run the edge finder against.



The two drill bits were used again for the 3mm clearance hole being pressed against a table tee slot to line up the head and run the edge finder against then the hole was drilled and the opposite side countersunk.



lastly the carefully noted stud hole positions can be used to locate the holes in the cylinder so they can be drilled and tapped making sure not to go too deep and break into the water space. You could spot the positions from the head but I seldom use that method since fitting the DRO.






Offline Jasonb

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Re: RLE Last & First
« Reply #10 on: August 12, 2023, 06:30:16 PM »
While up at the head end of the engine I thought I would get the last couple of small castings out the way. Starting with the silencer (muffler) halves these were held in soft jaws to turn the overall diameter and the cast surface was cleaned up a bit at the same time.



The halves could now be held the other way around and the flange machined to thickness, a cavity turned with a boring bar and in the case of the half that screws to the exhaust pipe that was drilled and tapped 1/8" BSP.



Most builders will probably opt to turn three spacers to fit between the halves but I left the flange on one half thicker so I could mill most of the material away and just leave three integral spacers.



The other casting that can be dealt with now is the Mk2 carb. I started by holding it in the 4-jaw and got the needle boss to run as true as possible then faced the bottom and the stub that can be drilled part way and tapped M8 x 1 before continuing the hole right through and tapping M4 x 0.5 for the needle.



Holding by the spigot in a square collet block I could index the casting about to drill the long inlet hole and also drill and tap for the pipe that joins carb to head.



The last thing to do was spot face the four mounting holes with am 8mm milling cutter and then drill through 3mm for the screws that will hold the carb to the fuel tank top. Make a note of where the hole positions end up so they can be used when tapping the tank.



A quick group shot of the exhaust parts and carb.


Offline Jasonb

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Re: RLE Last & First
« Reply #11 on: August 18, 2023, 07:15:21 PM »
The spigot on the bottom of the carb takes a non return valve that sits just off the bottom of the fuel tank. This is a fairly simple turning/milling job from a piece of brass stock I started by turning down one end of some bar to 8mm dia and threading M8 x 1 then drilled a cavity for the ball that acts as the valve. Next I milled a 10mm AF hex.



Now holding by the 8mm diameter the other end was turned and tapped so it could be screwed into the carb body and a small hole drilled to receive the end of the needle



The cap that goes onto the end of the M8 thread to retain the ball was turned and bored with a generous undercut to ensure the threads screwed all the way home.



The final part was the needle which was turned, threaded and knurled from some 303 stainless.

The was a discussion on ME forum about QCTP and how many tools are needed for a simple part or two. This pic shows the three parts and all the tools that were used in their making though there is one die missing.



Rather than trawl the supermarket or tobaconists shelves for a suitable flat round tin to use as a fuel tank I decided to make mine from scratch as I wanted the sides to have that bead rolled look that you often see on round sheet metal containers.

I started by cutting a slice off some 3" x 16g copper tube that I had and then turned a piece of MDF so that the tube was a tight push fit onto that so the ends could be finish turned. Then using a sharp DCGT insert the OD was reduced to leave two flat bands that were then rounded off by hand to represent the bead rolls.



A piece of 1.5mm brass sheet was sandwiched between two pieces of MDF and turned to diameter once the corners had been sawn off. I then  turned a 0.5mm tall spigot to a tight fit into the pipe. Having the pipe in place on the tailstock makes it easy to test fit without having to keep retracting the tailstock support. The remaining 1mm thick edge was rounded over with a file.



I did similar again for the bottom but left the sheet square



The four mounting holes were then drilled and used to make sure the work stayed put while the external shape was milled to incorporate the four mounting lugs.



The top was drilled centrally to clear the hex of the non return valve, Drilled and tapped for four screws to hold the carb body using the recorded DRO readings from when that was machined and finally a hole off to one side for the filler neck.



The parts could then all be soft soldered together, here is the finished tank complete with vented cap and the carb body in place. It won't be staying bare metal as I want it to look like a galvanised tank, might even go for a stencilled "Alyn" on the side.




Offline Admiral_dk

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Re: RLE Last & First
« Reply #12 on: August 19, 2023, 08:33:25 AM »
Interesting bit of fabrication Jason  :ThumbsUp:

Per      :cheers:

Offline Jasonb

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Re: RLE Last & First
« Reply #13 on: August 19, 2023, 01:35:33 PM »
Thanks, still got to get a bit of fabrication in there somewhere even with these casting kits :LittleDevil:

The other thing is it slows me down a bit otherwise I would be finishing too many models too quickly so that is why I like to add a bit of detail rather than just build off the plans. The casting sets do go so much quicker and I would hate to think of the cost if I were buying and completing 6-8 a year let alone where to put them all.

There will be a few more custom parts for this one along the way but some will be from castings that I will make patterns for as they may appeal to other RLE builders but I need the flywheel castings before I can finalise my design. In the mean time I've a little commission build to pass the time.

Offline Jasonb

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Re: RLE Last & First
« Reply #14 on: November 29, 2023, 06:57:50 PM »
It's about time I wrote up a bit more of this engine build.

With a view to getting the gearing done I made the cam gear post first. Starting with some stock that wa slarge enough to get the rectangular head out of I turned two diameters, the larger for the gear to run on and the smaller to go into the hole in the engine frame.



Then into the spin indexer to shape the clevis.



After reaming the pivot pin hole and milling a flat on the spigot the clevis was slotted for the latch and then rounded over



I spent some time working out different combinations of metric gear size and numbers of teeth and in the end settled on a 50/25T combination using MOD0.7 which are available online for those that want to buy or cutters can be bought quite cheaply.

I started by roughing out a blank for the cam gear and then machined the cam profile which I made with a little less lift to suit the lever lengths of the newer head layout that has the exhaust valve further from the rocker arm pivot



Then with the gear blank mounted on an arbor set about cutting the teeth using the rotary table with dividing plates



The 25T crankshaft gear was cut in a similar way except I did it on the end of a bar before reaming and parting off once the teeth were done.



I like to set the gear positions using the actual gears so with a temporary crank shaft in place the small gear was slipped onto that and the larger gear on an arbor held in the mill's collet chuck and the running fit and backlash adjusted by moving the engine's frame in the X axis. Once happy the DRO was zeroed.



After which a flat was milled and a hole drilled and reamed



The MOD0.7 25/50 combination has a slightly larger PCD than the original design's 1" which put the hole a bit out of ctr to the cast lug.



A bit of milling and filing soon had that sorted out and a hole drilled and tapped for the screw that retains the cam gear post.


Offline Chipswitheverything

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Re: RLE Last & First
« Reply #15 on: November 30, 2023, 09:21:09 AM »
Nice work on the gears and cam, Jason, and customary super detailed photos.  Presumably you keep some sets, or part sets, of DP gear tooth cutters of various sizes as part of your tooling store?..   Dave

Offline Jasonb

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Re: RLE Last & First
« Reply #16 on: November 30, 2023, 01:21:32 PM »
« Last Edit: November 30, 2023, 01:25:47 PM by Jasonb »

Offline Alyn Foundry

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Re: RLE Last & First
« Reply #17 on: November 30, 2023, 06:09:40 PM »
Sadly we’re hampering Jason’s progress as our new foundry is having difficulties with the flywheel pattern. Virtually every foundry has their own box/flask system for plated patterns. Our plates don’t fit….

Needless to say I’m indebted to both Jason and Colin ( Twizseven ) for their help in upgrading and replacing the stolen patterns with some very nicely 3D printed versions.

 :cheers:  Graham.

Offline Jasonb

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Re: RLE Last & First
« Reply #18 on: November 30, 2023, 06:13:28 PM »
Is it worth going down the new flywheel pattern route and then either have them as unplated which they seem to get done or stick them onto new plates of the right size.

Could add some nice bosses to three of the spokes for a pully at the same time.

Offline Jasonb

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Re: RLE Last & First
« Reply #19 on: December 10, 2023, 08:11:46 PM »
The rocker arm pivot is supplied as a casting but if used for the reversed valve layout does not put the pivot very centrally in the rocker arm so I spent a while studying the casting and working out a cunning plan that would still allow the casting to be used but shift the pivot point nearer to the valve.

The first job was to just take enough off the casting to remove the draft angles on the two edges that will mount to the head and also set these at 90 degrees to each other so I had a datum to work with.





I also skimmed the draft off around the pivot so that I could get a decent grip of the casting to bring it to thickness.





The casting was offered up to the head and a line scribed to mark where the mating area stopped and a ball nosed cutter used to tidy up that area to the line



Then it was out with the Sharpies to refine the shape, I left as much material as possible on the face that was machined earlier which moved the pivot point further from the head so the green pen marks where the opposite edge needs the excess material removed and the red shows where the screws will go to mount it to the head.



Drilling and reaming 3mm for the pivot pin



Then rounding around the pin hole on the rotary table



Last bit of machining for now was the slot for the rocker arm.



Finally the bracket in place, I have removed a bit of material from the head so it matches the depth of the bracket. After test running it will be bonded on and filleted with JB Weld so that it looks like an integral part of the head casting. redges will also be eased to make it look like a casting. There is still work to be done where the push rod goes but more of that later



« Last Edit: December 10, 2023, 08:15:50 PM by Jasonb »

Offline Jasonb

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Re: RLE Last & First
« Reply #20 on: December 18, 2023, 07:03:43 PM »
Continuing with things up at the head end the valves were done in my usual way by putting a small ctr drill hole into some 303 stainless bar so the stock could be supported with the revolving ctr and a DCGT insert used as it can get in nice and close.



A 2mm dia insert was used to form a fillet where the stem meets the head and also to cut the 45deg seat.



While the valves were still part of the bar stock I used that as a handle to give them a quick lap with some 600grit silicon carbide powder and oil.



They were then saw off and held in a collet to face the head and then fitted from the back of the collet so the ctr drill hole on the stem could be turned away.



The rocker arm was cut to my new shape to allow for the inlet valve to be closest to the push rod, the curve allowing it to reach over that to the exhaust.



While I had the CNC going I also did the gocernor latch arm and the cam follower which also had two holes tapped for the latch.





All three parts went back into the manual mill to have the excess holding material milled away



The cam follower was drilled to take a spigot that will be formed on the end of the push rod



The latch arm was thinned down either side for looks more than anything



Lastly the under cut of the latch was machined using a flycutter with a suitably ground HSS bit



The reduced thickness could then be slotted and CSK for screws with enough length to the slot so it's position can be adjusted.


Offline Jasonb

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Re: RLE Last & First
« Reply #21 on: December 23, 2023, 04:36:38 PM »
I decided that I would like a square push rod on my engine rather than the round one shown on the original drawings so a length of 4mm keysteel was ordered. A spigot turned on one end so that the bronze cam follower could be Loctited to it and the other end was drilled and tapped to take a small threaded adjuster. Rather than fiddle about with a small part in the 4 jaw I just drilled a bit of aluminium to the across corners distance of the rod and after sawing a slot down the side used that as a split bush.



The engine was screwed to the machining plate once again and clocked in true before finding it's horizontal ctr line.



I slipped the cam gear and it's pivot into place and touched off on the side of the gear then zeroed the DRO. I could then set my other heights relative to that.



I could then mill off the excess from the cylinder mounting flange and the rocker pivot bracket followed by a 4x4 slot for the rod to run in.



A few M2 tapped holes for the retaining blocks completed the work that needed to be done in that setup.



The two retaining blocks were just suared up from some off cuts of brass, drilled for bolts and a small ctr drilled hole added for a drop of oil to be applied. I knocked the corners off after the photo with a small file so that they looked like cast blocks.






Offline Jasonb

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Re: RLE Last & First
« Reply #22 on: February 11, 2024, 04:21:45 PM »
Another thing I wanted to add to my RLE was a pulley on the non governor side. I will modify the spokes of the cast flywheel to allow one to be fitted but while waiting for those decided to make the pulley.

I have quite a few 5kg cast weights from a multi-gym and although it is not the best cast iron in the world I thought it would do for this job. I piece was cut from one of the weights with my Femi bandsaw and then held in the 4-jaw to get it to the basic shape, here the inside has been turned with a 3degree "draft" to the edge and an insert with 0.8mm radius was used to leave a fillet between the inner edge and what will be the mounting lugs for that cast look.



I then held it the other way round in the 3-jaw and machined off the remaining corners before transfering to the Cuts Nice Curves (CNC) machine to shape the mounting lugs and drill their holes.



I probably should have gone 1mm lower with the profile cut as the "step" that can be seen is the fillet left from using the 0.8mm radius cutter.



It was not a problem as I had intended to go over the inner "cast" surface with the Dremel to texture it a bit so did the remaining fillet at the same time.



I wonder what is hiding in the other bits of that weight :thinking:



<a href="https://www.youtube.com/watch?v=YghxCw-0vu8" target="_blank">http://www.youtube.com/watch?v=YghxCw-0vu8</a>


Offline Jasonb

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Re: RLE Last & First
« Reply #23 on: February 22, 2024, 10:42:39 AM »
The two flywheels arrived at the beginning of the week, they did look a bit rough and had a fair amount of thin flash so the first thing I did was to take a small cross pein hammer and carefully chip the flash off. This shows the one on the right after chipping and the left as delivered.



I then fettled the flywheel, I like to do this before any machining a sit saves marking the finish turned rim if you intend to leave that bright. It was mostly done with files and then a quick tickle with the Dremel equipped with a grinding bit, again one on the right has been fettled. There is a little more to do between the spokes where they meet the hub.



Where possible I like to hold flywheels by the inside face of the rim and get that to run true as it is not  a surface that is going to be machined, this is another reason to clean them up first. With the 3-jaw's jaws reversed it fitted easily and was just tapped on the side until it ran with minimal wobble.


My machining sequence was:

Rim OD, Rim Side both these done with CCGT inserts using the holders that make use of the two "spare" corners.

I then changed to a boring bar with 0.8mm corner radius CCGT insert and flattened off the side of the inner rim, this ended up 1.75mm below the side face of the rim.

The hub was then faced, spot drilled, drilled 6mm with a stub length drill, opened out to 9mm and then a boring bar used to take it out to final 10mm dia using the crankshaft material as a plug gauge to get the fit right which is tighter than a nominal 10mm reamer gives.

Lastly change to a brazed tip tool with 1.5mm nose radius, set the topslide to a few degrees and clean up the OD of the hub. Knock off all corners with Lathe file.



To do the other side I changed to the 4-jaw and got the flywheel OD running true before machining Rim side, recessed side, hub face, hub OD.



With two done it was time for a trial fit


Offline Jasonb

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Re: RLE Last & First
« Reply #24 on: February 23, 2024, 06:37:08 PM »
I needed a way to mount the belt pulley described a couple of posts previously so clamped the non governor side flywheel to the mill table and located it's centre and ensured two opposite spokes were along the Y axis. The DRO made quick work of spotting, drilling and tapping the three holes at 120deg spacing and then I went round again with a 3-flute milling cutter to form a counterbore.



Some short lengths of 10mm steel were drilled M3 clearance and then bonded into the counterbores with JBWeld and left to set for 48hrs.



Once set the flywheel went back into the 4-jaw on the lathe to have the three bosses machined to length and also a small step turned that would locate the ID of the pulley.



and with the Pulley in place.



J

PS If you buy one of those Alyn Foundry stickers that can be seen bottom right of the last photo they give you a set of castings free. Stickers are not cheap though:LittleDevil:

Offline kuhncw

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Re: RLE Last & First
« Reply #25 on: February 24, 2024, 12:15:54 AM »
Nice work, Jason.  I attach pulleys to flywheel spokes also, but my spacers are loose.  Thanks for the hint to hold them in place with JB Weld. 

Chuck

Offline Jasonb

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Re: RLE Last & First
« Reply #26 on: April 09, 2024, 07:17:58 PM »
I was not that keen on the look of the governor weights as shown on the drawing which replicate the old Gramaphone governor weights that Graham used on his original nore the bent metal bracket that swing on. So I drew something up along the lines of what I did on the 1/5th scale vertical IHC Famous many moons ago.

The bracket was fabricated from two pieces, first a flat plate that will fit around the crankshaft and attach to the inner face of the flywheel hub with screws.



To keep the clevises at each end lined up they were machined from one piece that then had the central section machined away after silver soldering.





I neglected to take a photo of the actual weights but they were turned from 8mm rod having a taper at each end which was blended into a parallel central section and then flat tongues milled at the extremities for  the springs and adjusters. 4mm rod was soldered to these and at the other end of the rods were the blocks with the pivot holes and fingers that locate in the spool, first photo shows these pivot/fingers being machined



Add a couple of pivot pins and these are the main governor parts



The adjusters were turned from 4mm rod down to 2mm and threaded before milling the head flat, cross drilling for the spring and rounding over once they had been cut from the parent bar. The spring draw provided a couple of suitable springs that were cut to length and the ends bent into loops with two pairs of long nosed pliers.








Offline Alyn Foundry

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Re: RLE Last & First
« Reply #27 on: April 10, 2024, 11:54:07 AM »
Many thanks for the update on your R.L.E. engine Jason.   :ThumbsUp:

Nice to take a ‘ virtual ‘ trip to the workshop, something I fear will not happen here for several months to come.

 :cheers:  Graham.

Offline Jasonb

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Re: RLE Last & First
« Reply #28 on: April 10, 2024, 12:22:08 PM »
Hope it won't be too long for you.

Should have "Gassie" ready to show you in the next week or two.  ;) That should speed up your recovery and make up for not being able to get into the shop.

Offline Jasonb

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Re: RLE Last & First
« Reply #29 on: May 25, 2024, 05:04:03 PM »
As mentioned in my "Gassie" thread with that engine finished I could return to the RLE

With all parts complete it was time for a test so valve and ignition timing was set by eye as the flywheel was rotated by hand and then ready for a try. It did not have much life and after checking for a spark my thoughts turned to fuel as I could not smell much and there was no sign of flooding with the needle valve wound right out.

Squirting a bit of fuel into the carbs air intake did get a few pops as did heavily choking the intake with my finger but no sustained runs.

After a break for a bit of lawn cutting I went back into the workshop after lunch and altered the fuel jet so the end sat further into the air passage and that did the trick.

Here it is with the governor springs tight which I quite often do for initial tests, just be ready to shut it down if the engine starts to race away. Bit lumpy and erratic but at least it was running.

<a href="https://www.youtube.com/watch?v=Ru9dvNeVIxg" target="_blank">http://www.youtube.com/watch?v=Ru9dvNeVIxg</a>

After a bit of fiddling with needle valve and ignition timing it started to improve enough to slacken off the governor spring adjusters. Still stuttering a bit when it wants to hit but should improve with a few more tweaking sessions. It is really making a lot of compression to the point of being difficult to pull the flywheels over TDC so may skim a bit off the piston or see if the o ring beds in a bit more.

Now where did I put that can of paint :D

<a href="https://www.youtube.com/watch?v=5rUDsfwFj7o" target="_blank">http://www.youtube.com/watch?v=5rUDsfwFj7o</a>


Offline Michael S.

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Re: RLE Last & First
« Reply #30 on: May 25, 2024, 06:18:46 PM »
It's going very well.
At some point I'll have to build a small engine like this.
Maybe a set of castings from Torsten Schür.

Michael

Offline Jasonb

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Re: RLE Last & First
« Reply #31 on: May 25, 2024, 07:03:43 PM »
I've only machined flywheels from him, some of the nicest iron I have ever machined. He has some quite nice engines too.

Offline Jasonb

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Re: RLE Last & First
« Reply #32 on: August 03, 2024, 08:34:46 PM »
With the engine now proven to run it was time to think about how to mount it, I've done a few on wooded sleds and a few on 4-wheeled carts so for a change I decided to do a 2-wheeled "sack barrow" type similar to what you see the IHC Tom Thumb mounted on.

The wheels seemed the obvious thing to start with. Some ERW tube provided the rims, some 16mm round bar the hubs and some 8mm S275 black bar was cut into circles and the spoke profile milled into them.



They were then silver soldered together after which the hub was bored out to final size which ensures the hole is true and concentric to the rim should anything have moved during soldering.



The axle bolsters were fabricated from some steel angle and rectangular bar, hub retailing collars turned from 16mm bar and the handle bent up from 5mm steel solid bar.



A box was needed for the ignition and battery so some maple wa smachined down to 4mm thick and the mill used to cut the finger joints



Who needs glue with a fit like this


Offline Alyn Foundry

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Re: RLE Last & First
« Reply #33 on: August 05, 2024, 03:01:16 PM »
Always nice to see a new engine running Jason.  :ThumbsUp:

I was wondering if you were going to minister to the water hopper logo? As you’re aware that was an early casting from the  Rhuddlan foundry. Some 30+ years ago. Later engines had a new photo etched pattern with the Alyn diamond having a raised border.

The barrow frame will definitely make it look a nice authentic exhibition piece.

For the benefit of our readers what form of ignition have you employed for this project?

 :cheers:  Graham.

Offline Jasonb

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Re: RLE Last & First
« Reply #34 on: August 05, 2024, 03:13:07 PM »
Thanks Graham

It was tempting to machine off the cast name plates as there were some areas where the detail was a bit soft but I decided to keep them. There is still some additional "signwriting" to be unveiled, just done the last item - drip fee doiler so should have some photos later in the week.

I have gone with my usual S/S CDI ignition from Roy Sholl. It looks like these will continue to be available as someone new has taken them on as Roy retired. I will use a simple adjustable timing bracket clamped around an extended main bearing and a "peg" on one of the flywheel spokes to male contact with it.

https://cncengines.com/

I did also buy one of those spark generators you posted a video of on FB but will try that on something else. Maybe you could do a youtube version of that video to post here?

Offline Alyn Foundry

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Re: RLE Last & First
« Reply #35 on: August 05, 2024, 03:33:07 PM »
Welll…. Funnily enough I just did.

<a href="https://www.youtube.com/watch?v=3_U38qnyTC0" target="_blank">http://www.youtube.com/watch?v=3_U38qnyTC0</a>



 :cheers:  Graham.

Offline cnr6400

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Re: RLE Last & First
« Reply #36 on: August 05, 2024, 05:18:57 PM »
Thanks for posting this. Who is the manufacturer please? are they currently available? I don't use Facebook, so it would be great if you could ID the unit here. Thanks.  :cheers:
"I've cut that stock three times, and it's still too short!"


Offline cnr6400

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Re: RLE Last & First
« Reply #38 on: August 05, 2024, 07:50:21 PM »
Many thanks Graham.  :cheers:
"I've cut that stock three times, and it's still too short!"

Offline Jasonb

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Re: RLE Last & First
« Reply #39 on: August 09, 2024, 07:18:41 PM »
With the woodwork completed and some paint on the metal that is another one finished.

Still needs some tinkering to slow it down, it is making a lot of compression and really has a kick when it fires. Also want to get it picking up faster once the governor latches out.











<a href="https://www.youtube.com/watch?v=Km6jV3xrK2E" target="_blank">http://www.youtube.com/watch?v=Km6jV3xrK2E</a>

Offline Chipmaster

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Re: RLE Last & First
« Reply #40 on: August 09, 2024, 07:28:54 PM »
Marvellous work and incredible finish.  :ThumbsUp:
Andy

Offline Krypto

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Re: RLE Last & First
« Reply #41 on: August 09, 2024, 07:33:58 PM »
Marvelous work and quite a fine runner!

Did you make the cylinder oiler or is it off the shelf?
My Workshop Blog:  https://doug.sdf.org/

Offline Alyn Foundry

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Re: RLE Last & First
« Reply #42 on: August 09, 2024, 07:49:20 PM »
Words fail me at present Jason.  It will take me some time to take in all th nuances….   :ThumbsUp:

As usual your workmanship shows through every detail.

The R.L.E was designed to be an engine simply built by the average machinist but your vision has taken it several levels.
 :cheers: Graham.

Offline Kim

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Re: RLE Last & First
« Reply #43 on: August 09, 2024, 07:51:36 PM »
Another beautiful engine, Jason!  Nicely finished too! :ThumbsUp: :popcorn:

Kim

Offline Jasonb

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Re: RLE Last & First
« Reply #44 on: August 09, 2024, 07:58:06 PM »
Thanks all

The oiler is similar to the one I made for the Robinson, I like the cup shape more than the usual flat brass bottom and straight sided glass.

https://www.modelenginemaker.com/index.php/topic,7440.msg168708.html#msg168708

Offline Krypto

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Re: RLE Last & First
« Reply #45 on: August 10, 2024, 02:18:09 PM »
Thanks for the link!

It's a nicely done like the rest of the engine!
My Workshop Blog:  https://doug.sdf.org/

Offline Michael S.

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Re: RLE Last & First
« Reply #46 on: August 10, 2024, 02:48:19 PM »
Hello Jason,

I can only congratulate and take my hat off!
A very nice running engine.

Michael

Offline Admiral_dk

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Re: RLE Last & First
« Reply #47 on: August 10, 2024, 08:08:03 PM »
Amazing result and a beauty that will only get even more attractive as the wood darkens over time + Great runner  :praise2:

Per          :cheers:

Offline Roger B

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Re: RLE Last & First
« Reply #48 on: August 12, 2024, 11:55:17 AM »
Excellent  :praise2:  :praise2:
Best regards

Roger

Offline Chipswitheverything

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Re: RLE Last & First
« Reply #49 on: August 13, 2024, 08:48:10 AM »
Just caught up with the last part of the build log : This is a beautiful engine and as always, superbly finished and presented, super project.  Dave

 

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